What is balloon framing?

[DavidLeBlanc]

I've always thought it was just another name for conventional framing, but from reading here, it appears to be something different...?

[glenn-k]

Studs go bottom to top w/ let in ribbon to support second floor joists.

[DavidLeBlanc]

I'm still not clear on the difference, if any between balloon and conventional framing.

I don't know enough about conventional framing to see any difference between it and the drawing posted above.

[Rayn]

In conventional framing the studs are long enough to create one story.  For a two story house you have two layers of flooring and studs.  

In balloon framing the studs are two story in length,  so on top of the subfloor you raise 16ft (or so) studs.  I guess this where the balloon phrase comes from - a big empty two story tall framed structure.  Then you "hang" the joist for the second story inside on a narrow strip of wood and nail them to the studs.

I had an old house that was balloon framed,  it was wonderful for running electric lines from the attic to the basement!

[glenn-k]

I believe you have to put in fire blocking at 8 feet also since there would otherwise be an appx 16' open space.

I think you are allowed to count the space up to the  bottom of the ceiling (between the second floor joists) as your 8' ceiling height (joists can drop to about 7') saving a little height.  Going from memory on this - might not be good info--- :-/ however it is what I did at my other place.

Balloon Framing



Platform Framing



Pics credit www.housingtoronto.com

[jraabe]

Great diagrams!

It helps to remember that with balloon framing you "blow up" the walls all the way to the roof. Floors are hung off the balloon frame.

In platform framing (now "standard" framing) you built a platform all the way to the outside of the walls at each floor.

Balloon framing was invented first and many old buildings went up and put the roof on before building the floors.

When all the trees were straight grain old growth there were lots of great long studs (not anymore).

After lots of deadly fires it was realized that the wall cavities made great chimneys so fire blocking was required every 8'.

Platform framing is now standard since studs are shorter and for most crews it is easier to build the platforms as you go up. Wall sections are normally framed on the platform and then tilted up into position.

Balloon framing is still used in places where the strength of the tall studs help stabilize short walls as in the 20' wide 1 1/2 story cottage.
http://www.jshow.com/y2k/listings/50.html

PS - Most codes require that a habitable room have a minimun headroom of 7'-6". If the ceiling is a beam and decking situation, and beams are 3' or more apart, then the beams can be as low as door headers - 6'-8" and the ceiling counted to the bottom side of the decking.